The best
food for a cat is a mouse, fish, or bird.
Cats evolved from desert ancestors, who derived all their liquid from their prey and did not have to drink. Many of the cats of the present day still don't drink enough, so the best diet for most cat's is an all canned diet or a home-made diet. Cats do not have any requirement for grains at all!
Good canned brands include: Evo/Innova, Wellness, Nature's Variety, and the equivalent. Please choose grain-free varieties.